diff --git a/CHANGELOG.md b/CHANGELOG.md
index 1d0f233..35d68f9 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,12 @@
 # Changelog
 
+## [1.5.4](https://github.com/googleapis/python-iap/compare/v1.5.3...v1.5.4) (2022-10-07)
+
+
+### Bug Fixes
+
+* **deps:** Allow protobuf 3.19.5 ([#137](https://github.com/googleapis/python-iap/issues/137)) ([c5fd70f](https://github.com/googleapis/python-iap/commit/c5fd70f7168a5a87a52afb25a399a6990ab2c9e0))
+
 ## [1.5.3](https://github.com/googleapis/python-iap/compare/v1.5.2...v1.5.3) (2022-10-03)
 
 
diff --git a/setup.py b/setup.py
index 152cb90..70915cc 100644
--- a/setup.py
+++ b/setup.py
@@ -21,13 +21,13 @@
 
 name = "google-cloud-iap"
 description = "Identity-Aware Proxy API client library"
-version = "1.5.3"
+version = "1.5.4"
 release_status = "Development Status :: 5 - Production/Stable"
 url = "https://github.com/googleapis/python-iap"
 dependencies = [
     "google-api-core[grpc] >= 1.32.0, <3.0.0dev,!=2.0.*,!=2.1.*,!=2.2.*,!=2.3.*,!=2.4.*,!=2.5.*,!=2.6.*,!=2.7.*",
     "proto-plus >= 1.22.0, <2.0.0dev",
-    "protobuf >= 3.20.2, <5.0.0dev",
+    "protobuf>=3.19.5,<5.0.0dev,!=3.20.0,!=3.20.1,!=4.21.0,!=4.21.1,!=4.21.2,!=4.21.3,!=4.21.4,!=4.21.5",
     "grpc-google-iam-v1 >= 0.12.4, <1.0.0dev",
 ]
 
diff --git a/testing/constraints-3.7.txt b/testing/constraints-3.7.txt
index b9be78d..d977db9 100644
--- a/testing/constraints-3.7.txt
+++ b/testing/constraints-3.7.txt
@@ -7,4 +7,4 @@
 google-api-core==1.32.0
 proto-plus==1.22.0
 grpc-google-iam-v1==0.12.4
-protobuf==3.20.2
+protobuf==3.19.5